Nearly a quarter of all people playing, coaching or refereeing professional football personally know a gay player, according to new research into attitudes towards homosexuality in the game.

It also finds that almost eight out of 10 fans thought openly gay players would have the same positive effect on football as black players did in the 1980s and 90s when racism in the sport was tackled.

The findings are likely to raise expectations that football will soon follow other professional sports and see a top player come out. In recent years, rugby union, hurling and tennis have seen star players reveal that they are gay while at the height of their careers. But the survey, conducted by the University of Staffordshire, suggested such a move for a professional footballer would not be without risks.

Of the professional players, coaches, managers and referees who know gay footballers currently playing the game, a third believe they would face abuse from other players if they came out. Almost four out of five think they would face hostility from fans.

No professional footballer has ever come out in the UK while still still playing at the highest level. In 1990 Justin Fashanu, Britain's first £1m black player, announced he was gay after his career had, in effect, finished and he was playing semi-professional football.

A number of Fashanu's former team-mates said gay men had no place in a team sport. His brother, John, the ex-Wimbledon striker and now TV presenter, publicly disowned him, although he later retracted his comments.

Max Clifford, who is rumoured to have been consulted by at least three gay professional footballers, has revealed that he has advised footballers not to come out because the sport is "steeped in homophobia".

But just under 10% of fans questioned in the survey expressed hostility to homosexuality and resented any liberalisation in attitudes towards gay players witnessed in other sports. Ellis Cashmore, professor of culture, media and sport at the University of Staffordshire, who conducted the research, said for most fans the only thing that counted was a player's performance on the pitch. "One fan told us: 'I'd rather have a gay player who can play than a straight one who can't.' And this is a typical view, not just from supporters but from everyone associated with football," he explained.

Gareth Thomas, a former Wales rugby union captain who now plays rugby league, made headlines last year when he announced he was gay while still at the peak of his professional career. Of those football fans questioned in the research, more than 52% believe the greatest cause for a change in attitudes in the game would be a Gareth Thomas-type player coming out. A campaign backed by leading players was also considered by almost 31% to be influential.

One fan who completed the survey of 3,000 people explained: "A player finally having the courage to ruin their career by coming out [would change attitudes]. But it will be the end of their career as anything other than a 'gay footballer'."

Another suggested the move could even prove profitable. "He could make a lot of money [as] the first gay footballer." But only, "when football joins the 21st century".

Two-thirds believed at least one professional footballer would announce he is gay in the next five years.